Electric lamp holder



May 23, 19335. J R, PULLON llfiflQBQQ ELECTRI C LAMP HOLDER Filed July 16, 1929 INVENTOR 5%, .ZZ EwZ Patented May 23, 153313 7 1 UNITED STATES PATENT OFFFICE JOHN ROBERTSON PULLON, OF LONDON, ENGLAND ELECTRIC LAMP HOLDER Application filed July 16, 1929, Serial No. 378,801, and. in Great Britain July 20, 1928.

This invention relates to improvements in tween the lugs which may conveniently electric lamp holders of the type more eshave ribs 9 formed thereon to engage inrepecially intended to be attached to the ends cesses, or grooves h in the insulating block of flexible conductors in such a manner that or ribs may be formed in the insulating 5 the same are'brought into electrical contact block to engage in grooves in the lugs. One 55 with spring pressed contact pins mounted in part (Z of the insulating block is provided a block of insulating material comprised in with slots or recesses z'to receive spring conthe holder, the lamp being pressed against tact pins 7' held therein by the cooperating and held in contact with these pins by pins part 6 and the conductors is attached to the 10 on the lamp cap engaging in bayonet slots pins j pass out through slots or channels Z 60' in the holder. forming extensions of the recesses z'in which The said invention comprises an improved the spring contact pins are lodged. Howmethod for attaching the ends of the flexever, if desired, the recesses may extend into ible conductor to the spring contact pins, an each part of theblock. improved form of insulating block in which The two parts 01, e of, the insulating block 65 the contact pins are held, and a novel form having been placed together with their ends of lamp holder collar appropriate to the form in alignment and holding between them conof the insulating block. tact pins j in the recesses 2', can be inserted The accompanying drawing shows how the in the ring a, the faces f passing to a portion said invention can be conveniently and adbetween the lugs c which having some de- 7 vantageously carried into practice. In this gree of resiliency allow the grooves h to endrawing gage the ribs g. These grooves and ribs are Figure 1 is a side view and however not essential to the construction as Figure 2 a sectional view of a lamp holder the lugs alone would operate as stops to prein accordance with this invention. vent the cylindrical part of the block from Figure 3 is an end view thereof. passing out of the ring at this end thereof.

Figure 4 is a detail view showing one part The two parts of the insulating block and of an insulating block comprised in the holdalso the ring may be tapered or of wedge er with contact pins and conducting wires shape decreasing in size towards the top. 30 laid therein. This facilitates insertion of the block in the Figures 5 and 6 are perspective views of ring. For example the block andring may difierent forms of spring contact pin. be formed with flat portions or grooves and As shown in this drawing, the lamp holdribs, or may be of oval form and in such cases er comprises a ring (0 havin the usual baythe lugs, if desired, can be entirely dispensed onet slots 6 formed therein to receive the with.

pins of a lamp cap. This ring may be pro- The block can alternatively be divided vided, if required, with the usual screw transversely or obliquely transversely to its threaded portion to receive a shade supportaxis, the pins being held in holes formed to ing ring. At the ends of the lamp holder prevent the pins passing out of the same opposite to that in which the bayonet slots while the two parts of the block are held are provided, lugs 0 are provided integral together. I with the ring a and preferably bent inward- Each of the contact pins has two or more ly substantially in the manner shown in Figholes m drilled substantially diametrically ure 2. An insulating block (1, 6 divided on a through the pin at diiierent points along its 5 plane substantially parallel to the axis of end and preferably having their axes arthe block. is adapted to be held in this ring ranged in angularly separated axial planes. a and has a cylindrical or slightly tapered The endof a flexible conductorlc can then be portion fitting therein and a reduced part threaded through one of the holesand. then providing flattened faces f intended in the through a second or more holes in succession 50 use of the holder to occupy a position beso as to be secured therein by the lapping of the conductor wire as it is passed from one hole to another, as shown in Figure 5. The end of the wire can be tied to, threaded through, twisted around or looped on another part thereof, to firmly secure the wire and to ensure a good electrical contact.

Slotscan be employed instead of holes or springclips can be attached. Owing to the compression which can be exerted on the blocks d, e by the ring a and through them 011 the contact pins, both holes and slots could be dispensed with, or one hole or one slot employed, but two are preferable. Any slot can be cut so as to forma small tongue m Figure 5, capable of being pressed against or towards the main bodyof the pin j in which it is cut.

The spring :contact pins with the wires are firmlyclamped in the recesses in the insulating block between the two parts thereof when the latter are inserted into the ring a, and thering is prevented from being drawn oft fromthis block in ordinaryusage by the lugs c or bythetapering or .wedge shape portion of the rin reventin the c lindrical t; '3

portion of the insulating block passing out oftheholder at this end. The recesses in the insulatingblock may be of a=tapered, angular or wedge shape so formed that'the pins may be firmly-clamped between the twopart-s 0f the block.

Thearrangementofthe ribs 9 on the lugs oientering the grooves-in the insulating block (Z, e ensures the adjustment of the block to the right position withinthe ring to allow the cap of a lamp to be inserted into the ring a with thelamp pins properly engaged in-the bayonet slots 1) and the contactplates of the lamp cap in electrical contactwith the outer ends of the spring pins j. The travel of the spring pins allows-asubstantial variation ;in.the position of said contact plates longitudinally without loss of effectiveness whilst slight inward projections in the ring a engaging in slots .in the blocks as is usual in "existing lamp holders would ensure acorrect circumferential position. v

The slotsor channels can be so constructed as to grip the conductors throughout the length of the slots or by transverse ribs across the slots but these slots are preferably sufficiently deep to allow free pay of theconductors, the object being to prevent the wires from beinggripped tightly at any one. point where the wire is liable to-bebentthrough any substantial angle, as such tight gripping and bending ata particular point has a tendency to cause breakage of the wire at that point. I I

In case it is desired to :screw the lamp holder onto a wallfitting or-like support the insulating blocks andring can be made with enlarged portions whichare not necessarily cylindrical or are formed with ribs or grooves, the enlargement being at the end away from the bayonet slots and the blocks being inserted from that end. At the end of the blocks at the enlarged end within the ring a space may be provided to take surplus wire.

In lieu of a separate ring one or both of the insulatingblocks can be extended so as to formaring with bayonet slots'to receive the lamp cap. The two portions of the block can be fixed together by a screw passing through them transversely or by sliding one portion into a slot in the other or into a tapering ring froming part of the other or into an undercut groove in the other portion.

One insulating block'can be used instead oftwo either with bayonet slots in it or fitted into a ringhaving bayonet slots.

When only a single block is provided, the wires are inserted through holestherein and are then attached to the spring contactpillars which are then drawn-upwards by-the wires to positions within the-block. Each spring contact pillar is prevented from'entering the block beyond a predetermined distance either by a tapered formation of the holeinto which it fits or by ashoulder on thepin of greater diameter than the hole or'a pin-or bar extending across the hole. In this form the spring contact pins and the holes into which they fit are preferably made to taper towards their upper ends. Alternatively either the contact pins or the corresponding holes can eitapered at parts thereof so-that by rotating eachpin aboutits longitudinal axis it can be jammed tightly in the hole. Moreover the pins and holes may be of a more orless oval.

cross section so that by rotating the pins as above mentioned they will be firmly-held in the holes by a-wedging action or frictional engagement. The pins or holes can in some cases be advantageously provided with either circumferential, spiral, longitudinal or transverse ribsor grooves.

I claim 1. A lamp holder comprising a ring slotted to receivelamp cap pins, lugs onthe said ring remote from the slots, an insulating block slidable axially in the ring, the said block being divided on a plane parallel to the axis of the ring and comprising a cylindrical portion and a portion provided with flattened faces clamped between the said lugs interengaging .means between said lugs and said flattened faces for holding said block against axial movement-in said ring, and spring contacts clamped between the parts of the divided block.

2. A lamp holder comprising a ring slots ted to receive lamp cap pins, resilient lugs on the said ring remote from the slots, an. insulating block divided ona plane parallel to the axis of the ring and comprising a portion fitting and slidable within the said ring and'a portion clamped between'the said lugs, said lugs having ribs 011 their inner sides and said last-named portion of the block having notches to receive said ribs, and spring contact pins clamped between the parts of the divided block.

3. A lamp holder comprising a ring slotted to receive lamp cap pins, resilient lugs on the said ring remote from the slots bent inwardly, and an insulating block divided on a plane parallel to the axis of the ring and having a portion fitting within the ring and a portion of smaller size provided with horizontal grooves and clamped between the lugs, ribs 011 the lugs to engage said grooves and spring contact pins clamped between the parts of the divided block.

at. A lamp holder comprising a ring slotted to receive lamp cap pins, resilient lugs on the said ring remote from said slots, an insulating block divided on a plane parallel to the axis of the ring, the said block comprising a cylindrical portion slidably fitting within the said ring and a flattened portion with horizontal grooves therein clamped between the said lugs, ribs on the lugs to engage the said grooves, and spring contact pins clamped between the parts of the diavided block.

5. A lamp holder comprising a ring having a part thereof shaped to receive a lamp cap and a part thereof of different shape to provide a shoulder, an insulating block divided on a plane parallel to the axis of the ring and fitting within the ring and held against longitudinal movement in one direction therein by engagement of part of the block against the said shoulder, lugs on said ring engaging and pressing the parts of the block together and locking them against longitudinal movement in the opposite direction, and contact pins clamped between the parts of said block, each of said pins having a transverse Wire-receiving passageway.

6. A lamp holder comprising a ring slotted to receive lamp cap pins, lugs on said ring remote from the slots, an insulating block divided on a plane parallel to the axis of the ring and slidably fitting within the ring, ribs on said lugs for pressing the parts of the block together and locking them against longitudinal movement, and spring contact pins clamped between the parts of the said block, each contact pin having a passageway for retaining part of a conductor wire attached to the pin in a position transverse to the axis of said pin.

7. A lamp holder comprising a ring having a part thereof shaped to receive a lamp cap and a part thereof of diflferent shape to provide a shoulder, an insulating block provided with horizontal grooves and divided on a plane parallel to the axis of the ring, said block fitting within the ring and held against longitudinal movement in one direction therein by engagement of part of the tudinal movement in the opposite direction,

and contact pins clamped between the parts of said block, each of said pins having a transverse Wire-receiving passageway.

JOHN ROBERTSON PULLON. 

